1. Field of the Invention
The present invention relates generally to a window covering, and more particularly to a cord controller of a window covering.
2. Description of the Related Art
Window coverings, such as window blinds, usually have a top rail, a bottom rail, and a blanket or slats between the top and bottom rails. Conventional window blinds have a cord to be operated to fold or unfold the window blind. FIG. 1 shows a conventional cord controller 1 mounted on the top rail, including a base 2, in which a roller and a brake wheel are provided. A plurality of cords 5 pass through a space between the roller 3 and the brake wheel 4. It may fasten or loose the cords 5 by controlling the brake wheel 4. Such cord controller 1, however, still has some drawbacks, including:
1. The cords move relative to the roller 3 and the brake wheel 4 when the window blind is folded and unfolded. It will twist the cords 5 and the twisted cords interfere with the roller 3 and the brake wheel 4 that the cords 5 is hard to be pulled.
2. The purpose of the roller 3 is to reduce the friction of the cords 5. It is impossible to mount plural of rollers in the base. It needs an axle for the roller to rotate. However, the rusting axle 3a or dust on the axle 3a will cause the roller 3 hard to rotate, and therefore, it will increase the friction between the roller 3 and the cords 5. This problem is not easy to find that it always misses the best time to fix it. Besides, the axle 3a makes the roller hard to be assembled.